Whole of home assessments, what are they?
As part of the 2024 7 star energy requirements, most residential projects will require a new assessment and certification, known as a Whole of Home assessment. These are different to the normal 7 star energy rating (formerly 6 stars).
How a Whole of Home assessment differs from a 7 star rating is simple, a 7 star rating determines the construction of your home, or thermal envelope, and is based on things like your roof, walls and floor and how well insulated these are. For more information on 7 star ratings click here.
A Whole of Home assessment however does not deal with the external envelope of a home or its construction, but rather more the utilities and appliances you plan to have installed, examples being your heating and air conditioning, hot water service, pool and spa pump and even your cooktops and water fixtures. This is to determine that not only is your home well insulated and built, but also that your internal fixtures conform with sustainable design and living.
What process can I expect for a Whole of Home assessment?
Whole of Home assessments must be done in conjunction with 7 star energy ratings, as the amount of stars your home can achieve in an energy rating will determine how you approach your Whole of Home assessment. Whole of Home assessments will score your proposed design based on the efficiency of your appliances and internal fixtures, as previously mentioned.
A good example would be to say your home achieves a star rating of 8 stars, going above the minimum required 7 stars. This would mean that you have more flexibility in your approach to Whole of Home, since a greater star rating means your Whole of Home score requirement is reduced. You might decide it is more cost effective to install better insulation, to save money on having to install a better hot water system, thus experimentation on each design is key.
It is very important to note that while a star rating can impact the requirements for a Whole of Home assessment, this cannot be done in reverse, a Whole of Home assessment does not impact a homes star rating.
What if my Whole of Home assessment does not meet the minimum required score?
That’s no problem, our job as consultants is to ensure you have the best options for compliance on your residential project. You may find that sometimes its best to comply with the minimum 7 star energy standard, and instead install a solar panel on your residence, as opposed to reaching 8 stars for your energy rating but installing no solar panel at all.
There is no one ideal solution to all projects, which is why research and experience is key to achieving the best outcome for your project.
Some great information can be found on the NatHERS website found here, or additionally on the National Construction Code (NCC) website found here.